<!DOCTYPE html>
<html>
	<head>
		<meta charset="UTF-8">
		<title></title>
	</head>
	<body>
		<div>1</div>
		<div class="box">2</div>
		<div id="box">3</div>
		<div class="box">4</div>
		<div>5</div>
		<script src="http://libs.baidu.com/jquery/2.0.0/jquery.min.js"></script>
		<script type="text/javascript">
			var div_id = document.querySelector("#box");
			var div_class1 = document.querySelectorAll(".box")[0];
			var div_class2 = document.querySelectorAll(".box")[1];
			var div_arr = $("div");
			//转换为jq
			div_id = $(div_id);
			//jq
			console.log(div_id);
			//js
			console.log(div_id[0]);
			console.log(div_arr);
			console.log(div_arr.get(4));
			$(div_arr.get(0)).css("background","red");
		</script>
	</body>
</html>
